title: Effects of passive versus dynamic loading interventions on bone health in children who are nonambulatory.
abstract: OBJECTIVE
  To investigate the effectiveness of a novel dynamic standing intervention compared with a conventional passive standing intervention on bone health in children with cerebral palsy who are nonambulatory.
  
  
  METHODS
  Four children in passive standers and 5 in dynamic standers were followed for 15 months (standing 30 min/d, 5 d/wk). Dual-energy x-ray absorptiometry scans of the distal femur were obtained at 3-month intervals to measure changes in bone mineral density (BMD), bone mineral content, and area.
  
  
  RESULTS
  Increases in BMD were observed during dynamic standing (P < .001), whereas passive standing appeared to maintain the baseline BMD. Increases in bone mineral content were observed in each standing intervention (P < .001), with dynamic standing inducing greater increases. Increases in area were comparable between interventions (P = .315).
  
  
  CONCLUSIONS
  Dynamic standing demonstrated the potential of moderate-magnitude, low-frequency loading to increase cortical BMD. Further investigations could provide insight into the mechanisms of bone health induced through loading interventions.
authors.affiliation: Human Performance and Engineering Laboratory, Kessler Foundation Research Center, West Orange, New Jersey 07052, USA. mdd7@njit.edu
authors.forename: Megan
authors.initials: M
authors.lastname: Damcott
authors.forename: Sheila
authors.initials: S
authors.lastname: Blochlinger
authors.forename: Richard
authors.initials: R
authors.lastname: Foulds
mesh_terms: D015502:Absorptiometry, Photon; D015519:Bone Density; D002547:Cerebral Palsy / Q000534:rehabilitation*; D002648:Child; D019988:Children with Disabilities / Q000534:rehabilitation; D005081:Exercise Therapy / Q000379:methods*; D005269:Femur / Q000502:physiology*; D006801:Humans; D008137:Longitudinal Studies; D011187:Posture; D016474:Weight-Bearing